Java Technology in Action

Fair weather ahead with Java

How many times have you found yourself without an umbrella in a downpour, because the weather report said it would be 60 degrees and sunny? The truth is, TV and newspaper weather forecasts are wrong about as often as they're right. And yet, we continue to depend on them because, well, there haven't been any other options. Until now. Thanks to some farsighted weather researchers at the University of Michigan and the advanced Java^™ programming language from Sun Microsystems, you can now interactively view the national weather picture on your desktop computer screen. Whether you're in Portland, Maine; Portland, Oregon; or anywhere in between, you can get immediate access to the latest weather information by accessing the Blue-Skies World Wide Web site. And that's important, because the one thing that always holds true about weather is that it's going to change ­ no matter where you are.

Nothing but Blue-Skies

The brainchild of three University of Michigan scientists who call themselves The Weather Underground, Blue-Skies is a Java Powered^™ application featuring the Interactive Image Format Viewer. The viewer is an applet that works with any Java-enabled Web browser. Blue-Skies site visitors can download the Interactive Image Format Viewer and view a wealth of graphical weather data drawn from a network of close to 300 Internet sites. By simply moving a mouse across an on-screen weather map, the Blue-Skies user can see current weather conditions throughout the nation, updated instantly.

The three scientists ­ Christopher Schwerzler, Alan Steremberg and Derek Price ­ also developed the underlying imaging technology, called Interactive Image Format, or IIF, with the initial goal of creating digital weather maps. The increasing popularity of the Internet fueled their decision to develop the IIF viewer in the Java environment and distribute it over the Web. The viewer applet works by interpreting IIF, thereby allowing Web servers to customize IIF Web pages on the fly to fulfill individual user requests ­ all without having to recompile the original Java code.

The Java language's ability to dynamically add content in real time makes it perfect for the highly interactive Blue-Skies application. As Alan Steremberg puts it, "With Java, the end-user experiences a sense of feedback and interaction that you just don't get from stationary HTML. You don't even have to click your mouse to gather new information."

Java enables big improvements

Blue-Skies was originally developed in the Macintosh environment which presented certain limitations. Developing for the Mac meant that the programmers had to write their own networking, image decompression and display code first. "And that was before we ever got to the interesting part of our application," Alan Steremberg recalls. "The Java version only took a few weeks to write, is more stable and has better networking and image support." Due to Java language's compact design, the IIF viewer applet is also half the size of previous software releases.

Perhaps the most important improvement is that Blue-Skies is now integrated with the prevalent World Wide Web browsers. "Blue-Skies for Macintosh worked as a helper application," Steremberg explains, "whereas the Java version is seamlessly integrated into the rest of our Web weather services."

A world of weather

The Weather Underground offers what is probably the most comprehensive collection of online weather services available anywhere. As sponsors of the WeatherNet, they provide links to thousands of up-to-date forecasts, color satellite images from Nexrad and other sources, and analysis tools ­ including the same ones used by professional meteorologists to predict the weather. Blue-Skies users can access all of this data, plus weather reports from ski destinations, tropical storm updates and general travel conditions. In addition, the WeatherNet delivers live, daily pictures of weather conditions in over two dozen cities and resorts in North America, through its innovative WeatherCams.

The Weather Underground has plans to expand its services even more in the near future. In addition to their free educational site made possible by the University of Michigan and the National Science Foundation, they will shortly launch a commercial site that promises to be an even richer source of weather imagery and weather-related information.

Java enables new uses

The Java language's robust, distributed architecture is an important part of this growth. Because the IIF viewer can be downloaded quickly, easily and free of charge to multiple platforms, The Weather Underground believes it will be particularly useful as a science teaching tool in schools. In fact, they've already devised an extensive meteorology curriculum for grades K-12, to speed the applet's acceptance for this purpose.

Soon The Weather Underground will be licensing its Blue-Skies engine and extending the technology into other fields. Schwerzler envisions the Java applet being used for applications ranging from seismic activity monitoring and national park information to campus directories and bus schedules. "In addition to real-time science data providers, like us, you could use the IIF viewer for any John Doe's really cool home page," he says.

Cross-platform support is a breeze

Choosing to rewrite the existing application in the Java language has made life a lot easier for The Weather Underground. "We rewrote our code in JavaJava^™ because we were finding that too much of our development potential was going to cross-platform support," Schwerzler says. "By making the switch to JavaJava^™, not only was the coding of the new viewer much quicker, but we also now have a version that will run on multiple platforms." Since they've switched to JavaJava^™, the programmers no longer have to maintain separate Macintosh and Microsoft Windows versions of the software in parallel, which was causing a significant resource drain. Schwerzler says that if he has to pick a single feature of JavaJava^™ that is most important to The Weather Underground, it is the language's platform independence.

Fast development cycles

Both Schwerzler and Steremberg were surprised at how quick the development cycle actually was. In large part, this was because of Java's object-oriented design. "Chris and I found that we were able to build on top of many of the classes that came with Java, instead of writing the code ourselves, as we did before," Steremberg says. They anticipate that maintaining the application and adding new features in Java will also be much simpler from now on.

Sun and Java improve the business climate

The outlook: Clear sailing

The future is indeed looking bright for The Weather Underground. As they make the move to their commercial site, they look forward to success with their Java Powered^™ applet. "Our fan mail from Blue-Skies users has been growing considerably," they report. They plan on showing off other uses based on the present Java applet, once their commercial site is firmly established. Until then, they might just spend a little time enjoying the fine business climate.